Pneumatic boat structure and method of manufacturing the same



. May 16, 1950 M. J. STURTEVANT 2,503,304

PNEUMATIC BOAT STRUCTURE AND METHOD OF MANUFACTURING THE SAME Filed June 28, 1946 6 Shegts-Sheet l INVENTOR.

MARK J. STURTEVANT ATTORNEY STURTEVANT PNEUMATIC BOAT STRUCTURE AND METHOD OF MANUFACTURING THE SAME May 16, 1950 6 Sheets-Sheet 2 Filed June 28, 1946 INVENTOR. MARK J. STURTEVANT BY PM ATTORNEY May 16, 1950 M. J. STURTEVANT 2,508,304

PNEUMATIC BOAT STRUCTURE AND METHOD OF MANUFACTURING THE SA E Filed June 28, 1946 6 Sheets-Sheet 5 28 v FIG. I?-

19 FIG. l8

FIG.8

INVENTOR.

V 32 BY MARK J. STURTEVANT mat ATTORNEY May 16, 1950 M. J. STURTEVANT 2,503,304

PNEUMATIC BOAT STRUCTURE AND METHOD OF MANUFACTURING THE SAME Filed June 28, 1946 6 Sheets-Sheet 4 4 FIG. ll '8 FIG. I2 22 2| FIG. I3

FIG. l4

INVENTOR.

MARK J. STURTEVANT.

BY z

ATTORNEY May 16, 1950 a M. J. STURTEVANT 2,508,304 PNEUMATIC BOAT STRUCTURE AND METHOD OF MANUFACTURING THE SAME Filed June 28, 1946 6 Sheets-Sheet 5 FIG. l5

' FIG. 2|.

INVENTOR.

MARK J. STURTEVANT ATTORNEY y 16, 1 M. J. STURTEVANT 2,508,304

PNEUMATIC BOAT STRUCTURE AND METHOD OF MANUFACTURING THE SAME Filed Jurie 28, ,1946 e Sheets-Sheet 6 5? 4| 5e L n i 38 FIG. l9

FIG. 20

INVENTOR.

MARK J. STURTEVANT Wfi ATTORNEY Patented May 16, 1950 UNITED STATES PATENT OFFICE PNEUMATIC BOAT STRUCTURE METHOD OF MANUFACTURING THE SAME Mark J. Sturtevant, Akron, Ohio, assignor to Wingfoot Corporation, Akron, Ohio, at corporation of Delaware Application June 28, 1946, Serial No. 680,184

4 Claims. 1

. such structures in the fiat.

One of the problems involved in manufacturing pneumatic boat structures and the like is the d'ifliculty of assembling together the several pieces of rubberized fabric material cut to specific patterns to form the several cooperating elements of the boat and to insure, after their assembly, against the loss of the inflating fluid from the completed structure. All of the individual pieces of fabric material which are cut to a predetermined pattern must be joined together in such fashion that upon inflation the members so formed will present a smooth, regular contour to the structure and retain the inflating fluid for a maximum period of time. It is essential to provide a simple yet satisfactory method of assembling the several pieces of fabric material together in such a way as to provide fluid-tight joints at all of those points where the parts are interfitted.

It is, therefore, an important object of the present invention to provide an inflatable boat structure and the like which possesses a smooth, regularly curved contour from the bow to the stern thereof.

It is another object of the present invention to afford a novel method of constructing pneumatic boat structures and the like by fitting together a plurality of pieces of rubberized fabric material cut to a given pattern on a flat surface in such fashion that when the resulting structure is inflated, it will assume the desired smoothly curved contour of the boat.

Another object of the present invention is to provide a simple and economical method of manufacturing' an inflatable boat structure and the like which readily adapts itself to mass production operations.

f It is a further object of'the present invention to provide an inflatable boat structure and the like embodying a plurality of stacked rail members, each of which comprises a smooth, generally continuously curved contour and is constructed of a minimum number of pieces of rubberized fabric material. 7 i

For a better understanding of the teachings of the present invention, reference should be had y to the drawings in which Fig. 1 represents a plan view of one type of pneumatic structure in the form of an inflatable boat embodying the teachings of the present invention. Fig. 2 is a side elevation of the boat illustrated in Fig. 1. Fig. 3 represents an enlarged vertical cross-section through the boat of Fig. 2 as seen from the line 3 3 therein with parts broken away. Fig. 4 is an enlarged partial vertical cross-section taken along the line 4-4 in Fig. 1. Fig. 5 is an enlarged fragmentary cross-sectional view as seen from the line 55 in Fig. 1.

Fig. 6 of the drawings is an enlarged fragmentary elevation of the assembly of the nose portion at the bow of the boat as seen from the line 6-6 in Fig. 1. Fig. 7 is an exploded fragmentary cross-sectional view with parts in elevation showing the joint of Fig. 6 as seen from the line 1-'l therein. Fig. 8 is an enlarged partial plan view with parts in section and broken away to illustrate the bow construction of the boat as seen from the line 8-8 in Fig. 2. Fig. 9 represents a partial cross-section in exploded form as seen from the line 9-9 in Fig. 2. Fig. 10 is a partial cross-section as seen from the line Ill-l0 in Fig. 16 illustrating the several fabric pieces disposed in exploded relation as they are assembled.

Figs. 11, 12, 13, and 14 illustrate strips of rubberized fabric material cut to patterns for assembly into the boat of Fig. 1. Fig. 15 illustrates a single continuous strip of fabric employed in fabricating the bottom rail member of the boat, said strip being formed by joining two pieces of fabric material at their ends. Fig. 16 illustrates the bottom rail member formed in the fiat with part of the fabric removed. Fig. 17 represents an enlarged cross-section along the line H-ll in Fig. 15 of one of the strips of fabric with a reinforcing tape in place adjacent each of its peripheral edges preparatory to fitting the several strips of fabric together. Fig. 18 is an enlarged cross-section along the line l8-l8 in Fig. 16 and illustrates the several superposed strips of fabric and tapes assembled into a com- .pleted boat element. Fig. 19 is a plan view of the joined flat strips of fabric employed in fabricating the top rail member of the boat. Fig. 20 illustrates the top rail member assembled in the flat with parts broken away. Fig. 21 is an exaggerated diagrammatic representation of the development of the ends of the fabric pieces.

In the drawings, Fig. 1 illustrates an inflatable boat I of the twin-rail type which embodies the teachings of the present invention and is characterized by a plurality of inflatable, generally A 3 tubular elements or rail members of substantially continuously curved contour extending from the bow to the stern. The boat I comprises a top rail member 2 and a bottem rail member 3, of which the former is preferably of slightly greater circumferential dimension than the latter so as to enable it to provide an overhanging barrier extending about the outer peripheral dimension of the bottom rail member for reasons which will be apparent as the descriptiompro ceeds. The boat I has a floor .Iliwhichicomprisesa: a series of axially extending tubes 5, all of which advantageously intercommunicate, for unitary inflation and are supportedby asheet of fabric 5 be, slightly elevated in those portions thereof which form the bow andiithe stern of the boat I upon inflation;

a After the first continuous oval-shaped strip of fabric I9 is completed, crotch or reinforcing tapes 10 28, 2 are-secured; in place on the fabric strip adjacent tobutispaced inwardly from the inner and outer marginal edges 28, 29, respectively, thereof, asshown in Figs. 16 and 17. The ends of. tliejreinforcin'g tapes' 26, 21, which are actually 6 secured to the under-surface of the bottom rai1"15 narrowha' ds on rubberized fabric material, are

member 3. I

The inflation of the boat I is accomplished bya any convenient means such, for example, .as they use of cylinders (not shown) of gas under pres sureor by means of a manual pump unit which maybe connected to the valvesflj 8; ands-of" the top rail memberfi; bottom rail member 3; andfloor '4'; respectively: A pair "of' oar locks' I0- afiixedftothe top rail? of theb'oat I' are pro joined by overlapping at some suitable point, as indicated by theireference numerals 30 and 3i, along the periphery of the strip of fabric I9. Next, the similar continuous oval-shaped strip of 29 fabric embodying thefjoined semi-oyalpieces 20 is directly superposed" on' tl'iestrip" I .Qasshown in Figs: l'fiiand- 18.

The folded over portions of'the reinforcing tapes} 26; 27 are'intirnately bonded" to, the sur= shown) to enableth'e'boatto be propelled: A number of D-'rings' I I, I2? and I'3'may advan tageously'be secured to thetop rail 2 ofthe boat" I for supporting auxiliarwequipment for driv tione'with respectto its inner ia lid OuT/el" marginal edges 32; 33" as in the -cas-e'ofthe strip I9: The fabric adjacen-tthe inner margina'l edges Zfi; 32" and. the outer marginal-"edg's fli- 33' is cemented in'gtheboat or'f'or theinsertion of rope hawse'rs firmly-together to form outwardlyprojectinig' lip In the manufacture'of the boat I' according to to the teachingsof the-invention; a'seriesof pieces of rubberized fabric material are cut in theportions- -3'4, ,35 as shown in Figs: 4-; 5" and-9 upon inflation of'railmember 3-;5 It will;'be4understood thatthe remmrin tapes 2s n er-mu e un. folded upon inflation ofthe rail member*'-3 i and p s d' s i1 a d' firs thereupon operat'e'inflthe manner'illiustratedi in stripofffabriclt 'shown inFig; 11 forms; together with" an identically-shapedstrip of fabric in -re-' versed form, the --bottomhalf ofthe bottom rail member S-of-the-boat I-.' Thesemi-oval shaped Figs; 4, 5} and*9 to sea-l thefjo'in-tsfformed atth'e lipportions 34 and 3-5;

Infittingtogether the several strip s of-material and 26 at theext'remiti'es I13 I 8* and 23, 24,

curved f portions" I5 and I 6- which terminatein generally concave extremities I'Iand I8 respec tively; Inthe formingf-of-'thecontinuous, gen erally'oval-sh'a-ped strip of-fabriwIS (see Fig. 15)

ar employed at the bow a-nol stern, respectively: Aswill be noted fionrFig: 15, the tap s te and 3'! 5 are secured-implaee over the overlapped ex tremiti es- I?" and m at the oppositeends'of the-- which-forms'thebott'om halfof'botto'mrail=mem =roval shhped strip of fabric I9. Portions" of} the ber'-3-off the boat I; the second stripof fabric I 4 has its ends -joined*with' the first' strip offabric I Iat the '-concave extremities I I and I S t/hereof, while thematerial is*1 aid{out-'in fiat formupon a suitablet'able or other workingsurfacea- Aswillbe-seen from Fig-g" 15; thestrips l 4;- when fitted together into the continuous oval shaped' strip of fabrio I9 form a comp'aratively smooth curved portion" corresponding to the-stern sec tapes-35"and'3-?= are permitted to' extend beyond" the inner and" outei peripl'ieral' edgesiii -ar d 2 Sof" the strip I9 to enable them to be doubl'd-b'ack'- the'secured' portions of saii'cl tapes'i Thus,

placed over stripp- I6; the overlapped extremities 231; 24 -Will' also-be aiTE-Xed to-' the apes- 36, 3'1'-in' the manner shown in Fig. 10. V

The strip of fabric 35 illustratedin -Fig. 13

tion ofthe-finished-boatywhile-the opposite end isgfiyajgfjri m a iot n pr ram- 4 1.

of" the strip is-- characterized by an ogival1y-- shaped portion a which becomes the bow of the boat; It-'-wil1-be understood that in view of the curvedshapeof the e'xtremities I-I- and lil of the two oppositelylaid-stripsof fabric I4} it is: nec -versed with=respeottcythe'other,--w

essary todistribute the excess material in the formof "small gatherslas; evenly as possible along the entire length of the-joint. The inflation of 1 the completed-boat element tends to take up :this-'- excessand the finished jointbecomes smooth;

The strip of= fabric zo shown m ne-,- 12 forms," together with an identical-strip of fabric, the "top;

portionof the bottom rail member 3.0f the boat I when their curved end portionsZI and 22 are- 35 the- -boati if 1 1 in-*that it 'h as curved errd portions 3Q and 4 El whiem are provided 'w-it'h': concave' -terminating edges" t! and 4%, respectively: Two" identical strips of fabric ma-terialj at', one of which *is re-" being joinedat the terrninating edges- 'I- X thereof? a continuous; 'iiBStaritialIy -oVa shaped strip of fabric 4'3 (see g2 l l wliicli comprisea the'bottonr' portion ofthe' to ail memb -"of The ova-l stiaped strip offa is substantially identical to that shown in F-lga 15 In Fig-5 14 ior tnegdrawings; the-strip or material 44 is generally similar in "apeto thatofthe:- strip-of fabric-'zmillustrated r r Fliga 12. 'I h st-ripj d together at the extremities 23'- and 24 ofia'brie-4Eis generally-=semi-ovalin Shape -and"is'- thereof in the shape of a con'tin'uous oval-shaped stripofffabric 25a Itwillfbe notedthat'the strip or fabric 201is providedwith con-vex:- extremities 23 andZWon the curved'fendi portions -2I "and*22;'

provided with curvilifiearly shaped end portiens 45 and *46 which posses-sterminatingedges lland" 48 of convex. form. It will?be understdod that v two identi'ai "strips"of fabric flionefof wliich is,

respectively These convex" extremities" 23 and reversed with respect tothe other, when-joined" 52 and 53 and the ends of said tapes are joined.

as at 54 and 55. As in the construction of the bottom rail 3, the reinforcing tapes 56 and 51 are applied to the overlapping ends 4| and 42 of the fabric strip 43 after which the excess ma.-

terial in said tapes is doubled back upon the secured portion.

The continuous oval-shaped strip of fabric 49 embodying the cooperating joined strips of fabric" 44 cut in the manner illustrated in Fig. 14, is next superposed on the strip of fabric 43 having the reinforcing tapes 56, 5|, 56, and 51 secured thereto. The several parts are then firmly pressed or stitched together and the marginal portions 52, 53, 58, and 59 extending beyond the reinforcing tapes 5!] and 5| and adjacent the edges of the material, are cemented together, thus forming the projecting lip portions 66 and 6|. The li portions 66 and 6| are sealed internally of the top rail member 2 by the reinforcing tapes 5| and 56, respectively, in the manner illustrated in Figs. 4 and 5 when the finished rail member is inflated.

Figs. 6, 7, and 8 are illustrative of a typical form of bow or stern joint in the fabrication of either of the endless rail members 2 and 3. It will be noted from Figs. 6 and 7 that the cemented together marginal portions 29 and 33 of the ovalshaped strips of fabric I9 and 25 are separated part way at one end thereof to receive the opposite ends of the same marginal portions when the extremities I1 and 23 of said fabric strips are fitted together and overlapped. The reinforcing tape 36 disposed internally of the finished rail member, in this case bottom rail member 3, serves to seal the overlapping joint between the several fabric strips upon inflation of the member. Fig. 8 illustrates the manner in which the internally disposed reinforcing tape 36 is joined at 62 and how the tape passes under the circumferentially extending tapes 26 and 21.

In the assembly of the boat structure I, the top rail member 2, as we have noted, is somewhat broader of beam and longer in its axial dimension than the bottom rail member 3 and, therefore, will tend to overhang the bottom rail slightly when it is arranged in vertically stacked relation thereto as indicated in Figs. 3, 4, and 5. When the top rail has been properly positioned with respect to the bottom rail member 3, it is secured in place thereon as by means of a pair of crotch tapes 63 and 64. The top rail member 2 thereby affords not only additional flotation stability to the boat structure I, but also protects the occupants of the boat against the wash which might otherwise enter the boat when in use on rough water. The floor 4 and its supporting sheet of fabric 6 are held in place upon the bottom portion of the bottom rail member 3 by cementing the marginal portions of the sheet in place and anchoring them as by means of a crotch tape 65 in the manner illustrated in Figs. 3, 4, and 5.

It may be found desirable to employ a scufling strip 66 which is aflixed to the portion of the top rail 3' adjacent the bow of the boat to enable the lip portion 66 to be folded over as indicated in- As previously indicated, the extremities I'I, I8,

4|, and 42 of concave form, as Well as the extremities 23, 24, 41, and 48 of convex form, are developed from the shape of the joints at the bow and the stern portions of the top and bottom rails 2 and 3 of the boat I in the manner illustrated in Fig. 21. It will be understood from this diagrammatic representation which is exaggerated to show more clearly the method of development that when the extremities of the joint are projected upon a plane, the bottom half of the rail member forms a concave pattern while the top half of the rail member forms a convex pattern for the extremities of the strips which are to be united. Thus, it will be seen thatthe concave extremities II, I8, 4| and 42 of the strips I4 and 38, respectively, must be cut to the generally concave configuration indicated by the reference numeral I I, while the several extremities 23, 24, 41, and 48 of the fabric strips 20 and 44, respectively, are cut to the convex pattern indicated by the reference numeral I2 in Fig. 21.

In this way, after the several patterns have been fitted together in the manner described in detail, the top and bottom rail members 2 and 3, respectively, present a smooth continuous curved contour extending from the bow to the stern of the boat as distingushed from similar boats embodying multiple rail construction, each rail of which has a plurality of segments in the shape of right cylinders. Moreover, the bow and stern portions of the boat will be elevated slightly upon inflation of the structure. This elevation of the bow and stern portions of the boat greatly facilitates the maneuverability of the boat when in service.

The pieces of fabric employed in the fabrication of the pneumatic boat structure of the present invention are described herein above as being cut to a semi-oval shape. It will be understood that this nomenclature contemplates a substantially curved piece of material in the form of a general- .ly semi-annular strip (see Figs. 11 to 14, inclusive). Accordin to the procedure described above one of these semi-oval strips is laid out flat and a second identical strip is reversed, laid flat, and joined at its ends with the first strip to form a first generally annular or endless strip (see Fig. 15). A second annular strip identical to the first is superposed upon the first and the two strips are then joined peripherally. The resulting endless tubular member assumes the shape of a modified torus upon inflation.

Numerous modifications of the boat structure may be made without departing from the spirit or scope of the invention. .By way of illustration, the boat structure I may be made up of any desired number of inflatable rail members arranged in vertically stacked relation. The structure may, for example, have three or more such rail members.

While in accordance with the Patent Statutes one best known embodiment of the invention has been illustrated and described in detail, it is to be particularly understood that the invention is not: limited thereto or: thereby, .b'uti that? thet-ine ventive scope is: defined: in the -appended claims;

I claim: 1. In" the. manufacture: of pneumatic: boat endrjoin'ts and adjacent but spaced' inwardly from thezmarginal edges: of. the firstof the strips of fabric, ,allcof'saiol. tapesbeing; afiixed to the same surface oti said strip; superposing on the first structures and the like embodying apllirality'oii strip alsecond continuous stripoffabric assem- Sta-cited; inflatable; raill members characterized by" ai -substantially continucusa curved contour from, bow to stern oflisaidl boat structure; thezmethodi. of constructing 3;.119411 member. comprising: the.

steps of cutting a plurality of piccesof rubberreinforcing tapesdisposednbetweenland bonded ized fabric material. toltwo different. patterns; assembling-two piecesof.theasamepattern to;f0rm.= a continuous vsubstantiallyflatstrip of fabricbyreversingnneof thepieces andljoining the-endsbied froin-tworpieces of fabrioof the other pattern in: su-bstamtialiythe; same, fashion .as the first strip was;formecl;and intimately bonding the superposed strips of v fabric" together with the 'tethe :contactingxsurfaces of the strips.

4 In the; manufacture of pneumatic boat structure'ssanct the like; embodying a plurality of stacked inflatable rail members characterized by of the two vpieces ee -h r; secu fi o o n a substantiallyzcontinuous: curved contourfrom tapes at the endj ointsandi adiaeeiet but spaced inwardly-J from v the: marginal edges of one ofiithe' stripsof'fabric; superposina' a secondl continuous fiatstrip 'of fabric on said i first strip; enema I bow toistern of said boatstructure, the method of: constructing arail' member comprising the stepsiof cutting'fourpieces in twovpairs of rub-v berized fabric material to a shape such. that at mately bondi the inner and outer-edg'esof the: least the encl portions thereofiare oi curvilinear superposed: strips together. with: the the reinforc-- ing tapes disposed betweeniand bonded to the: contacting sun. aces oi the strips.

2.lIn the. manufactureof pneumatic; boat structures-and the li e embody g a D1 y= O substantially, curved strip of fabric; laying out one stacked inflatable. rail members. characterized. by at substantially continuous curved: contour; from-bow: to'stern of said boat structure the: method of constructing a rail. member comprisform; th'eIpieces: in eachhpair bein of identical configuration; reversing one: of. the pieces of each pair; joiningitogether the ends; of the pieces.

in each p'air' of identical pieces tofornra closed,

of the closed strips of fabricin: substantially flat form; b'onding over theiend joints oi the fiat closed strip' offabricca tapei having adhesive on one surface-thereof and provided with portions ing-athe steps oil-cutting from rubberized fabric t i gb t dg t r strip,

Outer p p y ereofisupe posi' a on 'fi 4a, the" superposed closed strips of fabric extend-- stripe second/strip; and intimately bonding to gether the peripheral edges: of both-strips with thee tapes disposedbetween the strips and aflh'tedw to -the contactingsurfa-ces otthe strips;-

3.l In the' manufacture. of pneumatic boat=struc- 5;

tures and the like embodying a plurality of stacked inflatable rail members. characterized by a substantially continuous-- curved contour from how tostern of said boat structura theniethodl tern; reversing one of the two identical pieces of 55 Number each set-and ioining the ends-there'of-tdicrm im the fiat a first con tinuous,- generally oval -s-l-iapedstrip (if-fabric; securing rein-forcing tapes at thewhichsp'ortio'ns are'iolded back upon and at leastequal in length-tome bonded portion thereof;

applying in an area uniformly-I spaced from the inner an'd outer peripheral edges of the closed 31711166 ;strip of: fabric additional tapes doubled back upon-themselves; superposing-the other pair ofpieces in the formof a closedstrip of fabric up on the first menticned strip; adhesively bonding together the; inner and outer peripheral ecl ges of ing beyond: the tapes; and placing the fabric strips into intimate relation.

MARKJ. STURT-EV-ANT.

REL-anemone crane The; following references are or record in the 5 are of" this" patent:

'UNITED- STATES PATENTS of constructing-- a. rail member comprising theme Number Name 1 Date 671,502. Sultemeyer Apr. 19,1.1901 2,408,789

FOREIGNTPATENTS Gountry Date 326348 Ital-y May- 7, .1935 3 28524 Great-Britain -May 1, 1930:

Luisada 1 Oct. 8, 1946- 

